12-22-2011, 01:16 PM
Thanks for your kind words, Matt. 
When I paint steam locos, I usually remove the gearbox (and sometimes the motor, too) so that the mechanism can be rolled back and forth inside the spray booth. This permits all areas to be airbrushed evenly, with no patches of bare brass showing as the drivers rotate. During this operation, all of the valve gear gets painted, too, including the piston rods. After the paint has dried, but is not yet fully cured, I touch a small brush, laden with lacquer thinner, to the piston area while, at the same time rotating the drivers. This removes the paint, exposing the original plating.
Painting side rods and valve gear is easy using an airbrush, but most locos, even new ones, have been lubricated, which is not especially conducive to paint adhesion. I like to remove the drivers, side rods, and valve gear as a unit, then place it, along with the frame, cylinders and other running gear in a sinkful of hot water and dish detergent. This removes all lubricant, and, after a thorough rinse, the parts are set aside to air dry. I sometimes brush paint the frame and driver centres, then re-assemble everything for airbrushing.
The airbrushed assembly is allowed to dry for a few days, then the motor and gears are re-installed, and the mechanism is run for a few minutes, either on the workbench or on the layout. This short break-in removes any paint from areas where moving parts touch, and, because it's dry, allows it to fall away. With the bare metal re-exposed, lubrication can be applied, sparingly, of course.
I don't clean the wheel treads until all weathering is complete - no point in having to do this task more than once. For wheels, simply support the loco upside-down, attach power leads, then touch a brush loaded with lacquer thinner to each tread in-turn while it's rotating. Follow-up immediately with a touch from a clean dry rag to remove the paint and thinner.
Wayne
When I paint steam locos, I usually remove the gearbox (and sometimes the motor, too) so that the mechanism can be rolled back and forth inside the spray booth. This permits all areas to be airbrushed evenly, with no patches of bare brass showing as the drivers rotate. During this operation, all of the valve gear gets painted, too, including the piston rods. After the paint has dried, but is not yet fully cured, I touch a small brush, laden with lacquer thinner, to the piston area while, at the same time rotating the drivers. This removes the paint, exposing the original plating.
Painting side rods and valve gear is easy using an airbrush, but most locos, even new ones, have been lubricated, which is not especially conducive to paint adhesion. I like to remove the drivers, side rods, and valve gear as a unit, then place it, along with the frame, cylinders and other running gear in a sinkful of hot water and dish detergent. This removes all lubricant, and, after a thorough rinse, the parts are set aside to air dry. I sometimes brush paint the frame and driver centres, then re-assemble everything for airbrushing.
The airbrushed assembly is allowed to dry for a few days, then the motor and gears are re-installed, and the mechanism is run for a few minutes, either on the workbench or on the layout. This short break-in removes any paint from areas where moving parts touch, and, because it's dry, allows it to fall away. With the bare metal re-exposed, lubrication can be applied, sparingly, of course.
I don't clean the wheel treads until all weathering is complete - no point in having to do this task more than once. For wheels, simply support the loco upside-down, attach power leads, then touch a brush loaded with lacquer thinner to each tread in-turn while it's rotating. Follow-up immediately with a touch from a clean dry rag to remove the paint and thinner.
Wayne